This invention generally relates to vapor-dispensing devices, and more particularly, to a method and apparatus for positioning a wick material in a vapor-dispensing device.
There have been various methods devised to attempt to regulate the diffusion of volatile materials especially with regard to the vapor delivery of fragrances and/or deodorizers. Exemplary prior art devices which relate to this are U.S. Pat. Nos.: 525,646; 1,123,036; 1,129,897; 1,323,659; 1,377,909; 2,383,960; 2,507,889; 2,616,759; 2,657,090; 2,787,496; 2,797,844; 2,878,060; 2,961,167; 2,975,464; 3,104,816; 3,239,145; 3,550,853; 3,633,881; 3,679,133; 3,804,331; 4,014,501; 4,094,639; 4,413,779; 4,663,315; 4,739,928; 5,038,394; 5,647,053; 5,903,710; 5,945,094; 5,976,503; and 6,104,867. The primary function of these types of devices has generally been the counteracting of malodors through the delivery of aesthetically pleasing fragrance vapors, or facilitating the delivery of other vapors, such as insecticides or other compositions.
In general, vapor-dispensing products typically include a fragrance-reservoir and a transport system from which fragrance is evaporated into the surrounding air. For example, in such system the liquid to be evaporated is transported from a reservoir via a wick material partially immersed in the liquid. In such a system, in general, the liquid is transported through the wick by capillary action. Many of these systems, such as the system described in U.S. Pat. No. 6,104,867 (xe2x80x9cthe ""867 patentxe2x80x9d), include a housing unit into which the liquid reservoir is placed. The housing of such devices advantageously includes a heating unit.
In such devices, the heating element delivers kinetic energy to molecules of the liquid as contained in the wick, thereby increasing the rate of evaporation to obtain higher fragrance intensity and uniform delivery density over time. Typically, in such units, a plug unit is plugged onto a conventional electrical outlet, thereby causing the heating unit to heat the liquid and vaporized liquid that have been drawn up into the wick. The wick and/or bottle unit containing the wick are suitably configured to such that the wick material is placed, when completely assembled, in proximity to the heating element. For example preferably, in most such devices, care is taken to ensure that the wick material, and particularly the uppermost portion thereof extends at least into, or more preferably into and through the typically circumferentially arranged heating unit.
While devices so configured typically ensure effective vaporization of the liquid to be dispensed, various difficulties can be encountered through use of the devices. For example, as explained in some detail in the ""867 patent, one of these difficulties (addressed by the guidance and/or stabilization systems described in the ""867 patent) is that the wick may become damaged either during insertion, use and/or removal of the wick containing reservoir (e.g., bottle). For example, during insertion and/or removal of the reservoir (e.g., bottle) the wick may be caused to contact the heating element. Furthermore, movement of the reservoir (e.g., bottle) relative to the housing during use or otherwise may give rise to deleterious or disadvantageous interactions between the wick and, for example, the hearing unit.
Products currently on the market have utilized wicks constructed of compressed graphite, porous ceramic, or fibrous bundles. See, for example, U.S. Pat. No. 4,663,315 issued May 5, 1987 to Hasegawa et al, and U.S. Pat. No. 5,647,053 issued Jul. 8, 1997 to Shroeder et al. In these cases, the transport mechanism is capillary action of liquid passing through the structure of a wick, which in use, is contained within the heating element. Notably, and as discussed in more detail below, with momentary reference to FIGS. 1A and 1B and 2A and 2B, each of these exemplary prior art devices clearly require the wide material to be placed, when in use, well within the heating element, and often, beyond the heating element. (FIG. Nos. 1A and 1B are Figures from the ""315 Hasegawa et al patent, while FIG. Nos. 2A and 2B are Figures from the ""053 Schroeder et al. patent).
Various methods for connecting the fragrance liquid reservoir to a housing unit of a vapor-dispensing device have been developed and are known. Typically, such methods comprise simple snap-type mechanisms, as shown in the aforementioned ""867 patent, or screw-thread designs, such as are shown on the ""315 patent to Hasegawa. With such systems, particularly when used in a wick containing vaporizer, the wick may be damaged by being crushed or bent by careless interconnection, or be overheated by contact with the heating element during operation, due to instability and improper positioning of the wick material relative to the heating element. This same instability and improper positioning may cause uneven heating of the wick, result in diminished evaporative performance, and consumer frustration.
In attempts to minimize damage, overheating and instability, overcaps and other means of protecting the wick by covering the and supporting the wick, including the portion protruding through the heating element may be employed. However, instability and improper positioning still may cause uneven heating of the wick, result in diminished evaporative performance, and consumer frustration. Moreover, the overcaps can present additional costs to the units and bottles. Thus, there exists a need for a method for positioning a wick material in a vapor-dispensing device that addresses the disadvantages of the prior art.
While the way in which the present invention addresses the disadvantages of the prior art will be discussed in greater detail below, in general, the present invention achieves advancement in the art by providing a method and apparatus for selective positioning of a wick material in a vapor-dispensing device that facilitates effective fragrance vapor delivery while offering significant advantages in manufacture, assembly, product performance, and product safety.
For example, in accordance with one embodiment of the present invention through effective alignment and positioning of the wick relative to a heating element in a vapor-dispensing device, effective vaporization of the vaporizable liquid can be obtained without subjecting the wick material to possible damage due to contact with the heating unit of the vaporizer during insertion, removal and/or use. In accordance with one aspect of this embodiment, the wick is suitably selected and positioned such that sufficient surface area of the wick material is Suitably exposed to the heating unit to enable effective evaporation of a vaporizable liquid, but the wick height relative to the heating element minimizes the amount of surface area of the wick in proximity to the heating element. Additionally, the positioning can reduce the need for protective overcaps and other apparatus for protecting the wick.
Further benefits and advantages of the various aspects and embodiments of the present invention are described in detail hereinbelow.